Gate array and manufacturing method of semiconductor integrated circuit using gate array

ABSTRACT

In a gate array, a gate length is measured by dividing gate electrodes into groups according to their materials to distinguish between those groups. The shape of a contact pad portion ( 5 ) of a gate electrode ( 4 ) differs according to the groups. A difference described here appears as shape such as cutouts ( 6   a - 6   c ) or projections ( 6   d - 6   f ), which is distinguishable by a scanning electron microscope, for example.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention is related to a gate array and amanufacturing method of a semiconductor integrated circuit using thegate array, and especially to a gate array including a row composed ofgate electrodes each having different etching rate and a manufacturingmethod of a semiconductor integrated circuit using the gate array.

[0003] 2. Background of the Invention

[0004] In a conventional gate array, since gate electrodes of P-channeland N-channel transistors are of the same shape, at first glance, it isimpossible to distinguish between a row in which the P-channeltransistor is formed and a row in which the N-channel transistor isformed. For example, FIG. 11 shows a layout pattern of a structure of agate array generally called a “sea-of-gate”. A semiconductor chip isformed of various elements integrated on one semiconductor substrate. Inthe outskirts of the semiconductor chip 1 of FIG. 11, a pad 2 connectedto a lead line for electrically connecting with the outside of thesemiconductor chip 1, and an I/O buffer cell 3 for buffering, forexample, a signal to be exchanged between the semiconductor chip 1 andthe outside thereof, are arranged. At the central portion of thesemiconductor chip 1, gate electrodes 4 are arranged in arrays. To rowsC1 through C7 of the gate electrodes, the conductivity type of thetransistors are allotted in order, for example, “PNNPPNN”.

[0005] In a general logic device, a gate length is an important factorto determine transistor performance, so that measuring and managing agate length during process is very important. For a conventional device,since gate electrodes of P-channel and N-channel MIS transistors areformed of the same material, there is no need to distinguish the channeltype of the MIS transistors to measure the gate length.

[0006] However, when the gate electrode of the P-channel MIS transistoris formed of a P-type polysilicon and the gate electrode of theN-channel MIS transistor is formed of an N-type polysilicon, theiretching rates become different from each other due to the difference ofimpurity. Thus, for a proper management, it becomes necessary todistinguish between the P-channel and N-channel MIS transistors tomeasure the respective gate lengths. FIG. 13 is a graph for explainingvariations in gate length between lots of the semiconductor chip. Inthis figure, a closed circle indicates an average gate length of theN-channel MIS transistor; an open circle indicates an average gatelength of the P-channel MIS transistor; and the straight line attachedto those circles indicates a distribution range (for example, threetimes as large as a standard deviation). In the case of FIG. 13, thegate length is managed so as to fall in the range of ±0.05 μm centeredat 0.35 μm. From this figure, it is understood that, under the sameetching condition, the gate length of the P-channel MIS transistor isalways longer than that of the N-channel MIS transistor. Thus, theproper management is only possible with the distinction between theN-channel and P-channel MIS transistors.

[0007] Then, it becomes necessary to measure the respective gate lengthby making a distinction between the gate electrodes of the P-channel andN-channel MIS transistors. When the whole semiconductor chip 1 is withinthe visual field as shown in FIG. 11, the conductivity type of thetransistors in a region AR1, for example, can be quickly distinguishedas an N-type by counting the number of rows. However, when a part of theregion AR1 of the semiconductor chip 1 is enlarged by a scanningelectron microscope, for example, as shown in FIG. 12, to measure thegate lengths of the N-channel and the P-channel MIS transistors, itbecomes difficult to distinguish the channel type of the transistors inthe region AR1.

[0008] In the above-described conventional gate array and manufacturingmethod of the semiconductor integrated circuit using the gate array,when the gate electrodes are formed of materials having differentetching rate, the gate electrodes need to be separated into groupsaccording to their materials to measure the gate length. However, thereis no mark for distinguishing between the gate electrodes at the gateelectrodes or in the vicinity of the gate electrodes in the conventionalgate array. Thus, for an enlarged gate electrode, it is difficult todetermine which group the gate electrode to be measured, for example,belongs to, and thereby the processing time for measurement isincreased.

SUMMARY OF THE INVENTION

[0009] A first aspect of the present invention is directed to a gatearray comprising: a plurality of first rows formed by arranging aplurality of first MIS transistors on a semiconductor substrate; and aplurality of second rows formed by arranging a plurality of second MIStransistors on the semiconductor substrate, wherein there is adifference in shape of a predetermined structural member,distinguishable by appearances, between the first and second rows.

[0010] Preferably, according to a second aspect of the presentinvention, in the gate array according to the first aspect, thepredetermined structural member is a contact pad portion of a gateelectrode.

[0011] Preferably, according to a third aspect of the present invention,in the gate array according to the second aspect, the contact padportion of the gate electrode includes a protruding part; the protrudingpart in one row is arranged in a direction determined by a predeterminedrule; and the predetermined rule for the first row is different fromthat for the second row.

[0012] Preferably, according to a fourth aspect of the presentinvention, in the gate array according to the third aspect, theprotruding part in the first row is arranged in the opposite directionto that in the second row; and both center lines of the contact padportions in the first and second rows almost agree with the samestraight line.

[0013] Preferably, according to a fifth aspect of the present invention,in the gate array according to the third aspect, the protruding part inthe first row is arranged in the opposite direction to that in thesecond row; and both center lines of portions of the gate electrodes inthe first and second rows, except the contact pad portions, almost agreewith the same straight line.

[0014] Preferably, according to a sixth aspect of the present invention,in the gate array according to the third aspect, the predetermined ruleprovides a plurality of arrangements each corresponding to differentinformation.

[0015] Preferably, according to a seventh aspect of the presentinvention, in the gate array according to the first aspect, thepredetermined structural member is a field oxide film.

[0016] Preferably, according to an eighth aspect of the presentinvention, in the gate array according to the first aspect, thepredetermined structural member is a field shield electrode.

[0017] Preferably, according to a ninth aspect of the present invention,in the gate array according to the eighth aspect, there is a differencein the shape of a hole for body contact provided in the field shieldelectrode, between the first and second rows.

[0018] A tenth aspect of the present invention is directed to amanufacturing method of a semiconductor integrated circuit using a gatearray, comprising the steps of: forming a plurality of first rows byarranging a plurality of first MIS transistors on a semiconductorsubstrate, and a plurality of second rows by arranging a plurality ofsecond MIS transistors each having a gate electrode which is differentfrom that of the first MIS transistor in an etching rate of a material,the second row including a difference in shape, distinguishable by theappearance of the semiconductor substrate, from the first row; andmeasuring a gate length by distinguishing between the first and secondrows on the basis of the difference in shape while enlarging a gateelectrode.

[0019] In the gate array of the first aspect or the manufacturing methodof the semiconductor integrated circuit using the gate array of thetenth aspect, when the gate length is measured, for example, the gateelectrodes formed of materials having different etching rates can bedistinguished by the difference in shape between the first and secondrows. This prevents misjudgment of the material of the gate electrode tobe measured, and further shortens time to confirm the material of thegate electrode.

[0020] In the gate array of the second aspect, the first and second rowsare distinguishable by the shape of the contact pad portion of the gateelectrode, that is, only by the gate electrode. This brings about quickmeasurement.

[0021] In the gate array of the third aspect, the difference in shape iseasily distinguishable because the protruding part whose direction isexamined is relatively large in shape.

[0022] In the gate array of the fourth aspect, the source/drain contactsin the first and second rows can be positioned in the same straightline. Thus, the design for the position of the source/drain contactremains the same as before, which reduces the complexity of design.

[0023] In the gate array of the fifth aspect, the design for theposition of the contact arranged in the contact pad portion of the gateelectrode remains the same as before, which reduces the complexity ofdesign.

[0024] In the gate array of the sixth aspect, it is possible to transmitinformation necessary for measurement except that for distinguishingbetween the first and second rows, depending on the combination ofarrangements. This reduces the movement of the visual field when thegate electrode is enlarged, resulting in quick measurement when suchtransmission of information is required.

[0025] In the gate array of the seventh aspect, the first and secondrows can be distinguished by observing the field oxide film in thevicinity of the gate electrode, which brings about quick measurement.Further, since the design of the gate array remains the same as beforeexcept the shape of the field oxide film, the complexity of design canbe suppressed.

[0026] In the gate array of the eight aspect, the first and second rowscan be distinguished by observing the field electrode in the vicinity ofthe gate electrode, which brings about quick measurement. Further, sincethe design of the gate array such as the shape of the gate electroderemains the same as before except the shape of the field oxide film, thecomplexity of design can be suppressed.

[0027] In the gate array of the ninth aspect, the first and second rowscan be distinguished by observing the hole for body contact, in largenumbers for each row, formed in the vicinity of the gate electrode,which brings about quick measurement. Further, since the design of thegate array remains the same as before except the shape of the hole forbody contact, the complexity of design can be suppressed.

[0028] The object of the present invention is to simplify thedistinction between groups of enlarged gate electrodes by addinginformation of the grouping at the gate electrode or in the vicinity ofthe gate electrode, and thereby to shorten the processing time torecognize the gate electrode with the scanning electron microscope.

[0029] These and other objects, features, aspects and advantages of thepresent invention will become more apparent from the following detaileddescription of the present invention when taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0030]FIGS. 1A to 1F are plan views showing various structures of acontact pad portion in accordance with a first preferred embodiment ofthe present invention.

[0031]FIG. 2 is a plan view showing a structure of a gate array inaccordance with a second preferred embodiment of the present invention.

[0032]FIGS. 3A and 3B are diagrams for explaining arrangements of acontact in the contact pad portion.

[0033]FIG. 4 is a plan view showing another structure of the gate arrayin accordance with the second preferred embodiment of the presentinvention.

[0034]FIG. 5 is a plan view showing an array of the gate electrodes ofthe gate array in accordance with a third preferred embodiment of thepresent invention.

[0035]FIG. 6 is a perspective view for explaining a structure of thegate array in accordance with a fourth preferred embodiment of thepresent invention.

[0036]FIG. 7 is a plan view showing a structure of the gate array inaccordance with a fifth preferred embodiment of the present invention.

[0037]FIG. 8 is a perspective view showing for explaining a structure ofthe gate array in accordance with a sixth preferred embodiment of thepresent invention.

[0038]FIG. 9 is a plan view showing a structure of the gate array inaccordance with a seventh preferred embodiment of the present invention.

[0039]FIGS. 10A to 10O are diagrams showing various shapes of a hole forbody contact.

[0040]FIG. 11 is a layout showing a structure of a semiconductor chipwith the gate array formed thereon.

[0041]FIG. 12 is a partly enlarged plan view of FIG. 11.

[0042]FIG. 13 is a graph for explaining variations in gate lengthbetween lots of the semiconductor chip.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0043] 1. First Preferred Embodiment

[0044] With reference to FIGS. 1A to 1F, a gate array according to afirst preferred embodiment will be described. The important point of theinvention as to a structure of the gate array according to the firstpreferred embodiment is that the shape of a contact pad portion differsdepending on groups so as to add information of classification intogroups. Different gate electrodes which are made from materials havingdifferent etching rates belong to different groups, respectively. Thedifferent groups are classified according to the shapes the contact padportions. In FIG. 11, for example, rows C1, C4 and C5 are composed ofP-channel MIS transistors; and rows C2, C3, C6 and C7 are composed ofN-channel MIS transistors. Each row belongs to a group of C1, C4 and C5is called a row CC1; and each row belongs to a group of C2, C3, C6 andC7 is called a row CC2. The rows CC1 and CC2 comprise gate electrodesformed of a P-type polysilicon and an N-type polysilicon, respectively.FIGS. 1A to 1F are plan views showing a variety of structures of acontact pad portion according to the first preferred embodiment. Forexample, either of cutouts 6 a through 6 c or projections 6 d through 6f as shown in FIGS. 1A through 1F is formed at a contact pad portion 5of each gate electrode in the row CC1, while no cutout or projection isformed at a contact pad portion 5 of each gate electrode in the row CC2.The contact pad portion 5 is a wide portion provided at both ends of agate electrode 4. With such difference in the shape of the contact padportion 5 between the rows CC1 and CC2, it becomes possible todistinguish the channel type of a transistor, N-channel or P-channel, ofa gate electrode 4 within a visual field of a scanning electronmicroscope even if only one gate electrode is within the field. Thisprevents a misjudgment of the group, such as a conductivity type, of anobject of measurement, and also prevents measurement from taking a longtime to confirm the conductivity type of the object of measurement. Whenthere is a difference in the shape of the contact pad portion 5 betweenthe rows CC1 and CC2, the movement of the visual field to distinguishthe difference of the contact pad portions 5 is only limited to therange of less than one gate electrode. Thus, the processing time formeasurement can be sufficiently reduced.

[0045] Further, the same effect as described above can be obtained bychanging the shape of the contact pad portions 5 only of some gateelectrodes 4 in the row CC1, for example, every other one or two gateelectrodes.

[0046] Moreover, even if the contact pad portions 5 of both transistorsare altered in shape, the same effect can be obtained as long as theP-channel MIS transistor differs from the N-channel MIS transistor inshape.

[0047] Further, the present invention does not limit the shape of thecontact pad portion 5 required to obtain the effect of the firstpreferred embodiment. The contact pad portion 5 need not be of the sameshapes shown in FIGS. 1A through 1F. As long as it can be distinguishedby shape from the other when observed by the scanning electronmicroscope, the same effect as described above can be obtained.

[0048] Furthermore, one row, for example the row CC1, may include thecontact pad portions 5 in a plurality of shapes, for example,alternately in the shapes of FIGS. 1A and 1B. This makes it possible totransmit other information such as the number of rows or a specific rowrequiring measurement, and further, reducing the movement of the visualfield, for example of the scanning electron microscope, to confirm suchspecific information brings about quick measurement. Further, in thiscase, more portions can be measured during the same measuring time asbefore, which improves yield, for example.

[0049] 2. Second Preferred Embodiment

[0050] In the gate array according to the first preferred embodiment,either of the cutouts 6 a through 6 c or the projections 6 d through 6 fis formed to change the shape of the contact pad portion 5. On the otherhand, in the gate array according to a second preferred embodiment, thedirection of a protruding part of the contact pad portion 5 differsdepending on groups to distinguish the groups.

[0051]FIG. 2 is a plan view showing a structure of the gate arrayaccording to the second preferred embodiment. As shown in FIG. 2,protruding parts 7 of all gate electrodes 4 in the row CC1 are arrangedin the right direction, while those in the row CC2 are arranged in theleft direction. Thus, even if only one gate electrode 4 is within thevisual field of the scanning electron microscope, it is possible todistinguish between the N-channel and P-channel MIS transistors by thedirection of the protruding part 7. Further, even if only a part of thegate electrode 4 is within the visual field, only slight movement of thevisual field is enough to bring the contact pad portion 5 within thefield. Thus, the processing time for measurement is sufficientlyreduced.

[0052] In FIG. 2, the dashed-and-dotted line with the reference numeral8 is the center line passing a channel region of the gate electrode 4.As shown in FIG. 2, portions 4 a of the gate electrodes 4, except thecontact pad portion 5, in both rows CC1 and CC2 in the same column arearranged so that their center lines agree with the dashed-and-dottedline 8. That is, the center line passing the portion 4 a of the gateelectrode 4, except the contact pad portion 5, in the row CC1 agreeswith the center line passing the portion 4 a of the gate electrode 4,except the contact pad portion 5, in the row CC2. Thus, a source/draincontact 9 can be arranged in the same position as before. That is, thedesign of the source/drain contact 9 remains the same as before, whichreduces the complexity of design to be caused by the application of thepresent invention.

[0053]FIGS. 3A and 3B show examples of a contact 10 arranged in thecontact pad portion 5 having the cutout 6 a; FIG. 3A shows a normalcase; and FIG. 3B shows an abnormal case. A region 11 of FIG. 3Bindicates a portion of the contact stacked out from the contact padportion 5. In such case, the contact connects with other diffusionregions, and thereby an inferior device is produced. Thus, yield islikely to be reduced. On the other hand, in the structure with no cutoutaccording to the second preferred embodiment, the reduction of yield dueto such causes can be prevented.

[0054] Further, as shown in FIG. 4, the positions of the contact padportions 5 in the rows CC1 and CC2 of different groups may be arrangedin order along columns. In other words, the center lines of the contactpad portions 5 of the different lines CC1 and CC2 agree with each other.With such arrangement, the contact 10 is formed in the same position atthe contact pad portion 5. That is, the design of the gate contactremains the same as before, which reduces the complexity of design to becaused by the application of the present invention.

[0055] The selection of the structures shown in FIG. 2 or FIG. 4 is madeby the numbers of gate contacts and source/drain contacts.

[0056] 3. Third Preferred Embodiment

[0057] In the gate array according to the second preferred embodiment,the protruding parts 7 of all contact pad portions 5 in one row arearranged in the same direction. On the other hand, in the gate arrayaccording to a third preferred embodiment, one row includes theprotruding parts 7 arranged in different directions.

[0058]FIG. 5 is a plan view showing an arrangement of gate electrodes inthe gate array according to the third preferred embodiment. As shown inFIG. 5, the row CC1 includes gate electrodes 4 a, 4 b, 4 d and 4 e whoseprotruding parts 7 of the contact pad portions 5 are arranged in theright direction; and gate electrodes 4 c and 4 f whose protruding parts7 of the contact pad portions 5 are arranged in the left direction. Onthe other hand, the row CC2 includes gate electrodes 4 g through 41whose protruding parts 7 are arranged in the right direction. If therows CC1 and CC2 with such arrangement correspond to the P-channel andN-channel MIS transistors, respectively, it is possible to determine thechannel type of the MIS transistors of the gate electrode to be measuredeven in observation of the partly enlarged gate array. In the case ofFIG. 5, for example, whether the row belongs to a P-type group or N-typecan be determined by observing the directions of the contact padportions 5 of the gate electrodes at most in adjacent three columns.

[0059] In the structure of the gate array according to the thirdpreferred embodiment, the gate contact and the source/drain contactcannot be formed in the same position as before in both P-channel andN-channel MIS transistors, which a little complicates the designcompared to the structure of the second preferred embodiment. However,depending on a rule of arrangements, it is possible to include otherinformation except the information for determining the channel type ofthe MIS transistors forming the row.

[0060] For example, taking three columns as a set, the directions“right, left, and left” of the protruding parts 7 is regarded as “0” andthe directions “right, right and left” is regarded as “1”. In this case,the determination of “0” or “1” is made by the direction of the gateelectrode sandwitched between the gate electrode having the protrudingpart 7 arranged in the right direction and the gate electrode having theprotruding part 7 arranged in the left direction. Further, the end ofone set is determined by the gate electrodes at the left end arranged inthe right direction and the gate electrode at the right end arranged inthe left direction. Such division makes it possible to transmit otherinformation, such as the number of rows or a specific row requiringmeasurement, as the necessary information for inspection, and furtherbrings about quick measurement. Further, in this case, more portions canbe measured during the same measuring time as before, which improvesyield, for example.

[0061] 4. Fourth Preferred Embodiment

[0062] In the first through third preferred embodiments, the shape ofthe gate electrodes differs according to rows of different groups.However, a change may be made in the shape of other components in therow except the gate electrode. In the gate array according to a fourthpreferred embodiment, the shape of a layer formed below the gateelectrode (the shape of a field oxide film in this case) is altered.

[0063]FIG. 6 is a perspective view for explaining a structure of thegate array according to the fourth preferred embodiment. In the gatearray shown in FIG. 6, a row in which N-channel MIS transistors areformed and a row in which P-channel MIS transistors are formed areisolated by LOCOS isolation. Field oxide films 15 and 16 to be used inthis LOCOS isolation are formed below the gate electrode 4. A change inthe shape of these field oxide films 15 and 16 according to their groupsprovides the information that the conductivity type of the transistorsformed in the row CC1 differs from that of the transistors formed in therow CC2. To be concrete, a recess 17 is formed at an edge portion on theopposite side to the gate electrode 4. In the case of FIG. 6, one recess17 is provided every two gate electrodes 4. However, the presentinvention does not limit the number of the recesses 17, so that, evenwith a larger or smaller number of recesses, the same effect can beobtained as in the fourth preferred embodiment. Further, though employedto make a difference in shape between the field oxide films 15 and 16,the recess 17 may be substituted by a protruding part or others as longas the difference in shape can be distinguished by appearances. In sucha case, the same effect can be obtained as in the fourth preferredembodiment.

[0064] Since the shape of the gate electrode 4 remains unchanged bychanging the shapes of the field oxide films 15 and 16, there is no needto change the conventional design specification, which prevents thecomplexity of the manufacturing process.

[0065] 5. Fifth Preferred Embodiment

[0066] The gate array of the sea-of-gate type is described in the fourthpreferred embodiment. On the other hand, this fifth preferred embodimentis directed to a gate array in which one row is divided into severalfields. FIG. 7 is a plan view showing a structure of the gate arrayaccording to the fifth preferred embodiment. Shown in this figure arethe fields in the rows CC1 and CC2, respectively, with the other fieldsomitted. If the P-channel and N-channel MIS transistors are deposited inthe rows CC1 and CC2, respectively, for example, a mark 21 is providedon the outer periphery of the field to distinguish its conductivity typefrom the other. The mark 21 is formed by changing a plane feature of amask for forming a field oxide film 20 to modify the shape of the fieldoxide film 20. The present invention does not limit the position of themark 21 only to the angle of the field, as well as the number of marks.

[0067] 6. Sixth Preferred Embodiment

[0068] With reference to FIG. 8, the gate array according to a sixthpreferred embodiment will be described. FIG. 8 is a perspective view forexplaining a structure of the gate array according to the sixthpreferred embodiment. In FIG. 8, the P-channel and N-channel MIStransistors are deposited in the rows CC1 and CC2, respectively. Thegate array shown in FIG. 8 isolates transistors in different rows byfield shield isolation.

[0069] In order to distinguish the conductivity types of thetransistors, the widths of field shield electrodes 25 and 27 differ fromeach other. In the case of FIG. 8, the P-channel MIS transistor isdeposited in the row CC1 having a wide field shield electrode 25; andthe N-channel MIS transistor is deposited in the row CC2 having a narrowfield shield electrode 27. The difference in width between the fieldshield electrodes 25 and 27 corresponds to the difference in widthbetween insulating films 26 and 28 covering the field shield electrodes25 and 27, respectively, and can be observed by the scanning electronmicroscope, for example.

[0070] When the field shield electrodes 25 and 27 are formed of a P-typepolysilicon, an isolation breakdown voltage on the side of the P-channelMIS transistor is reduced in relation to work function. Thus, in orderto increase the isolation breakdown voltage under such conditions, it isfavorable to form the field shield electrode 25 wider than the fieldshield electrode 27. When there is some margin of the isolationbreakdown voltage, the field shield electrode 27 may be formed narrowerthan that in the conventional case, which is effective to improveintegration of the semiconductor chip 1.

[0071] On the other hand, when the field shield electrodes 25 and 27 areformed of an N-type polysilicon, an isolation breakdown voltage on theside of the N-channel MIS transistor is reduced in relation to workfunction. Thus, in order to increase the isolation breakdown voltageunder such conditions, it is favorable to form the field shieldelectrode 27 wider than the field shield electrode 25. When there issome margin of the isolation breakdown voltage, the field shieldelectrode 25 may be formed narrower than that in the conventional case,which is effective to improve integration of the semiconductor chip 1.

[0072] 7. Seventh Preferred Embodiment

[0073] Next, the gate array according to a seventh preferred embodimentwill be described with reference to FIGS. 9 and 10. As shown in FIG. 9,a change in the shape of holes for body contact drilled in the fieldshield electrodes 30 and 33 provides the information for distinguishingbetween the P-channel and N-channel MIS transistors. In FIG. 9, forexample, two rows of the gate electrodes 4, indicated by the referencenumeral 32, are composed of the N-channel MIS transistors; and two rowsof the gate electrodes 4, indicated by the reference numeral 35, arecomposed of the P-channel MIS transistors.

[0074] The shape of the hole for body contact 31 indicates that the gateelectrodes 4 deposited at both ends of the hole 31 belong to theN-channel MIS transistor, while the shape of the hole for body contact34 indicates that the gate electrodes 4 deposited at both ends of thehole 34 belong to the P-channel MIS transistor.

[0075] Even if only one gate electrode 4 is within the visual field ofthe scanning electron microscope, the shape of the hole for body contact31 indicates the channel type of the MIS transistor of the gateelectrode 4 within the visual field. This prevents a misjudgment of theconductivity type of an object of measurement, and further preventsmeasurement from taking a long time to confirm the conductivity type ofthe object of measurement. Further, since the shape or position of thegate electrodes 4 remains the same as before, the design of the gateelectrode 4 remains the same as well.

[0076] The shapes of the holes for body contact 31 and 34 may vary asshown in FIGS. 10A through 10O. Further, other information, such as thenumber of rows and a specific row requiring measurement, can betransmitted by combining those shapes, which brings about quickmeasurement. Further, more portions can be measured during the samemeasuring time as before, so that yield can be improved.

[0077] While the invention has been described in detail, the foregoingdescription is in all aspects illustrative and not restrictive. It isunderstood that numerous other modifications and variations can bedevised without departing from the scope of the invention.

I claim:
 1. A gate array comprising: a plurality of first rows formed by arranging a plurality of first MIS transistors on a semiconductor substrate; and a plurality of second rows formed by arranging a plurality of second MIS transistors on said semiconductor substrate, wherein there is a difference in shape of a predetermined structural member, distinguishable by appearances, between said first and second rows.
 2. The gate array according to claim 1 , wherein said predetermined structural member is a contact pad portion of a gate electrode.
 3. The gate array according to claim 2 , wherein said contact pad portion of said gate electrode includes a protruding part; said protruding part in one row is arranged in a direction determined by a predetermined rule; and said predetermined rule for said first row is different from that for said second row.
 4. The gate array according to claim 3 , wherein said protruding part in said first row is arranged in the opposite direction to that in said second row; and both center lines of said contact pad portions in said first and second rows almost agree with the same straight line.
 5. The gate array according to claim 3 , wherein said protruding part in said first row is arranged in the opposite direction to that in said second row; and both center lines of portions of said gate electrodes in said first and second rows, except said contact pad portions, almost agree with the same straight line.
 6. The gate array according to claim 3 , wherein said predetermined rule provides a plurality of arrangements each corresponding to different information.
 7. The gate array according to claim 1 , wherein said predetermined structural member is a field oxide film.
 8. The gate array according to claim 1 , wherein said predetermined structural member is a field shield electrode.
 9. The gate array according to claim 8 , wherein there is a difference in the shape of a hole for body contact provided in said field shield electrode, between said first and second rows.
 10. A manufacturing method of a semiconductor integrated circuit using a gate array, comprising the steps of: forming a plurality of first rows by arranging a plurality of first MIS transistors on a semiconductor substrate, and a plurality of second rows by arranging a plurality of second MIS transistors each having a gate electrode which is different from that of said first MIS transistor in an etching rate of a material, said second row including a difference in shape, distinguishable by the appearance of said semiconductor substrate, from said first row; and measuring a gate length by distinguishing between said first and second rows on the basis of said difference in shape while enlarging a gate electrode.
 11. The manufacturing method of the semiconductor integrated circuit using the gate array according to claim 10 , wherein the step of forming said first and second rows includes the step of forming a gate electrode with a distinguishable difference in the appearance of a contact pad portion of a gate electrode between said first and second rows.
 12. The manufacturing method of the semiconductor integrated circuit using the gate array according to claim 11 , wherein said contact pad portion of said gate electrode includes a protruding part; and the step of forming said first and second rows includes the step of forming a gate electrode so that said protruding part in one row is arranged in a direction determined by a predetermined rule which differs between said first and second rows.
 13. The manufacturing method of the semiconductor integrated circuit using the gate array according to claim 12 , wherein in the step of forming said gate electrode, said protruding part in said first row is arranged in the opposite direction to that in said second row, and both center lines of said contact pad portions in said first and second rows almost agree with the same straight line.
 14. The manufacturing method of the semiconductor integrated circuit using the gate array according to claim 12 , wherein in the step of forming said gate electrode, said protruding part in said first row is arranged in the opposite direction to that in said second row, and both center lines of portions of said gate electrodes in said first and second rows, except said contact pad portions, almost agree with the same straight line.
 15. The manufacturing method of the semiconductor integrated circuit using the gate array according to claim 12 , wherein the step of forming said first and second rows includes the step of forming a gate electrode in accordance with a predetermined rule which provides a plurality of arrangements each corresponding to different information.
 16. The manufacturing method of the semiconductor integrated circuit using the gate array according to claim 10 , wherein the step of forming said first and second rows includes the step of forming a field oxide film with a distinguishable difference in the appearance of said field oxide film between said first and second rows.
 17. The manufacturing method of the semiconductor integrated circuit using the gate array according to claim 10 , wherein the step of forming said first and second rows includes the step of forming a field shield electrode with a distinguishable difference in the appearance of said field shield electrode between said first and second rows.
 18. The manufacturing method of the semiconductor integrated circuit using the gate array according to claim 17 , wherein in the step of forming said field shield electrode, a distinguishable difference appears as the shape of a hole for body contact provided in said field shield electrode. 